Properties of Matter

Mushrooming marshmallows

Enrichment Activity for 5-11 11-14

What you need

  • Wine saver or coffee saver with pump
  • Wine bottle or coffee container
  • Marshmallows


  1. Put a handful of small marshmallows into the bottle or container.
  2. Put a stopper in the top and pump out as much air as you can.

Results and Explanation

The marshmallows should grow to become much larger. When you release the stopper they should collapse to their previous size.

These experiments have not been specifically safety tested for home use but we believe them to be safe if the instructions are followed. Adult supervision or direction is recommended as appropriate. All experiments are carried out at your own risk.

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